Mutation
by MargaritaDaemonelix
Summary: It's spreading beyond their control, faster than they can think. For the EFB perfect dream prompt.


MUTATION

By MargaritaDaemonelix

The first victim is, of all people, Elsword.

The townspeople had _told_ him to not run directly towards the plant, regardless of how strong his flames are, but stubborn as he is, that is _exactly_ what he does. With nothing holding him back, he runs right at the damn plant, throwing a flaming rune, and gets a face full of the gas released.

And now, he lies unconscious in the guild base, the tip of his nose purple and his lips slightly parted, as if seeking a breath of air. Everyone comes and goes, bringing fresh towels and water and medication, but nothing seems to help reduce his fever. Rena and Ciel take turns tending to him, replacing the cold compress that sits on his forehead and feeding him a trickle of water.

Every day, everyone comes to talk to him, to plead with him to wake up. Over the course of the week, his condition continues to deteriorate, and there's nothing they can do to stop it.

That is, until Elesis gets fed up with the fact that her brother is _dying_. She marches up to him, slaps him in the face, _hard_ , and yells "WAKE UP!" Loudly enough to make Rena drop her herbal ointment.

Slowly, the young leader of their team comes back to himself. His hair grows out the gray streaks, turning back into its natural vibrant red, and for a few hours a day, he actually regains consciousness.

"I was trapped in a dream," he says, when he's strong enough to stay awake for the majority of the day. "It was like the perfect reality - nothing was in our way, we finally stopped the demon invasion and the Henir cult people and all the bad guys, and the only thing left to do was to train."

"Then why'd you wake up?" Aisha asks, jotting down notes on his every word.

Elsword shakes his head, as if to get the remnant sleep out. "I was training in Ruben," he says, "and then Elesis came over, slapped me, and told me to stop training. That's when I realized it had to be a dream - the real Elsa would never tell me to give up on my goals. Especially not when I had all the time in the world to achieve them."

It's really a fluke, and only an experiment that happened to work out, but everyone thanks Elesis in earnest for saving her brother, and by proxy their entire team.

Aisha continues to take notes on Elsword's condition. The plant, she concludes, releases a virus that controls its victims' minds. Once they enter the comatose state, the plant will spin a perfect dream for them, one they'll never be able to leave.

To make matters worse, during the duration of that perfect dream, the plant siphons the life force out of its victim, using it to grow. If they never wake up… They'll never wake up.

"What a terrible plant," Lu sniffles. "We must destroy it at once. Ciel, fashion us some masks to prevent us from inhaling the virus."

They'll have to go back another day, hope it'll be enough to destroy the thing. Rena aptly names it the Black Mercy, and thus it begins to haunt them.

* * *

The next to fall victim to the Black Mercy is Ain, but none of them realize it until it's almost too late.

Raven realizes there's something sticking out of the priest's back, and then suddenly they're gathered around Ain's collapsed form, watching as the symptoms that struck Elsword return.

The Black Mercy, it seems, has adapted to their new gas masks, and is employing new tactics to destroy its assailants. The thing in Ain's back is a shimmering thorn, and when they manage to extract it, it's shining with rapidly blackening blood.

There is one very, very large difference between Ain's symptoms and Elsword's, though. Where Elsword entered a coma and just wouldn't wake up, Ain flickers in and out of existence. Sometimes, he'll start to lose colour and go translucent, and only when someone goes and attempts to wake him up does he return to the reality of the plane they're on.

"Is he flickering out of our reality?" Elsword asks, after he had to literally _yell_ to bring him back. "Did the Black Mercy mutate to cause him to do this? Or did he already have this ability beforehand?"

"It's a possibility, but I think he must have had powers like this before the Black Mercy got him. The fact that he's in a comatose state is causing his control over his own reality go haywire," Aisha says, which is really just Aisha-speak for "I really don't know what's happening, and I'm too scared to find out".

In the end, it's Lu that figures it out. A few hundred millennia of continuous learning gives her the knowledge to deduce that Ain is an agent of Ishmael, capable of phasing in and out of existence at the will of two beings - Ishmael the lady of life herself, and someone with strong ties to the El. That means just about everyone in their team. Glances are cast at Elsword, who literally radiates El energy, and Elesis, the chosen of the El Lady, but they gather up all the El they can find in their belongings, and bring it to Ain.

As they yell his name, louder and louder, his eyes finally snap open.

* * *

"The demon queen is correct," he says afterwards, sitting on the couch with a mug of hot chocolate in his hands. "I am an angel of Ishmael, sent to repair the cataclysm caused in the El explosion." He pauses. "If it weren't for the fact that you woke me up, I would have faded from existence forever."

He, too, dreamt of a perfect world, where he served at Lady Ishmael's side after serving his duty in Elrios. The only thing that woke him up and saved him was the sound of his allies, his friends, crying out for him.

However, this only means they need to act faster. The Black Mercy is still on the loose, and claiming more lives by the second. For every life lost, the virus it releases siphons life energy and gives it to the plant, allowing it to live on further.

"The Black Mercy mutates and adapts to exploit our weaknesses," Raven says, as they plot their attack. "So we need to be one step ahead of it."

"But that means we'll both need to be fast and protected against the plant, so lightweight armor is a must," Chung points out. "We'll build on the gas masks we already have."

* * *

They plan late into the night.

Rose, Eve and Add each contribute some designs for the armor, using their combined expertise to block out the virus for the most part. Ara and Aisha bind magic to their weapons, as a means of improving their offenses but also keeping up a defensive shield against the Black Mercy. Chung, Elsword and Lu sit crosslegged on the floor, stitching together fabric and steel plating to make suitable armor.

By the time Rena blows out the last candle and sends them off to sleep, it's already practically morning.

Still, if it means they'll bring an end to the terror of the Black Mercy, it's all worth it.

* * *

The final blow to the damn plant is dealt by Elsword, who jabs his sword into the roots and lights it on fire. "We've done it," he says, breathing heavily through his gas mask, smiling in relief. "We destroyed the Black Mercy."

The Elgang cheers wearily, in their mismatched armor.

And then it hits them.

A virus only needs to attach to a cell for it to reproduce. Between the thirteen of them, contact is all too frequent, and the virus has spread among them, eating away at their energy beyond their knowledge. Their joints stiffen, minds go blank, CPUs falter, and they topple like dominoes.

It seems the only adaptation that they hadn't though of was themselves. The Black Mercy, although destroyed and gone, still has one trick up its sleeve - it has now turned its murderers into its own weapons.

One by one, they fall into a sweet dream, the one they'll never leave, and their lives feed a new monstrosity, waiting to be awakened.

* * *

The cove that was once home to the Black Mercy is now home to a glowing blue tree. They call it the El's Aspiration in the nearby town.

Those who come near it may have the misfortune of contracting the virus it emits. Once they do, they fall into a sweet dream, the perfect dream that they'll never want to wake up from.

Only this time, their dreams are haunted by the ghosts of thirteen fallen warriors, begging them to awaken.

* * *

 **A/N: i have a math test tomorrow morning what am i doing with my life**

 **so yeah this is for the _perfect dream_ prompt on EFB, if anyone wants to join us hmu! the prompt itself is loosely based on the Black Mercy from the DC universe, but i took some creative liberties with the properties of the plant since i've done _way too much research on viruses ahahaha_**

 **and now back to math...**

 **~Marg**


End file.
